The present invention relates to a putter head and to a putter head set.
In a golf game, final putting often decides the game, and not only the golfer's capability of putting but also the performance and characteristics of a putter are one of the factors in deciding the game. The performance and characteristics of a putter includes, for example, the center of gravity and moment of inertia of the putter head, ease of finding a putting line, and ease of setting. The adjustability of the performance and characteristics of a putter according to the physical condition of the golfer on the play day and the kind and condition of the green lawn is advantageous to the golfer.
However, in order to obtain the performance and characteristics of a putter, it is necessary to form the putter head into a specific shape using a specific material. Depending on the skill level and the adopted theory of the golfer, various performance and characteristics of the putter are required, and also, individual golfers like different appearances of putters. Therefore, putter heads having a wide variety of designs have been developed. However, there are few putter heads available for which the golfer can adjust the performance and characteristics of the putter.
For example, Japanese Patent Application Publication No. 2001-224718 describes a putter head formed by combining four parts to change the center of gravity of the putter head. The putter head is configured so that the four parts consist of a body, two wing parts located on both sides of the body, and a bottom part, and by fitting protrusions of the bottom part in grooves formed in the body and the wing parts, the parts are connected to each other. By forming the right and left wing parts by using materials having a different specific gravity, the center of gravity of the putter head can be changed to the right or the left.
In the configuration described in Japanese Patent Application Publication No. 2001-224718, however, although the center of gravity of putter head can be changed greatly by changing the specific gravity of the right and left wing parts of putter head, it is difficult to greatly change the moment of inertia of the putter head. Also, in the configuration described in Japanese Patent Application Publication No. 2001-224718, the number of parts constituting the putter head is large, and therefore it is not easy to assemble a putter head having a strength capable of withstanding putting by using these many parts.
Also, Japanese Patent Application Publication No. 2005-66249 describes a putter head provided with a front half body having a face surface and an arcuate rear half body attached to the rear side of the front half body. The front half body is formed of a metal having a small specific gravity, and the arcuate rear half body is formed of a metal having a large specific gravity. Therefore, the moment of inertia around the center of gravity of putter head is high, and the sweet area of putter head is large. However, Japanese Patent Application Publication No. 2005-66249 does not particularly describe that the moment of inertia of the putter head is adjusted. Also, in the configuration described in Japanese Patent Application Publication No. 2005-66249, the front half body and the rear half body are fixed with two bolts, so that this configuration is still insufficient for the golfer to himself or herself adjust the moment of inertia easily.